EP2963334B1 - Light conductor assembly for use in a lighting device of a motor vehicle and motor vehicle lighting device with such a light conductor assembly - Google Patents

Description

• mindestens einen Lichteinkoppelabschnitt mit mindestens einer Lichteintrittsfläche zum Einkoppeln zumindest eines Teils des von der mindestens einen Lichtquelle ausgesandten Lichts,
• einen Lichtauskoppelabschnitt mit einer Vielzahl von entlang einer Rückseite der Lichtleiter-Anordnung angeordneten Lichtauskoppelelementen zum Umlenken zumindest eines Teils des eingekoppelten Lichts in Richtung eines Linsenabschnitts der Lichtleiter-Anordnung, und
• den Linsenabschnitt, der eine Längserstreckung quer zu einer Lichtaustrittsrichtung der Lichtleiter-Anordnung und eine in einem Querschnitt quer zur Längserstreckung konvexe linsenförmige Lichtaustrittsfläche aufweist, über die zumindest ein Teil des von dem Auskoppelabschnitt umgelenkten Lichts aus der Lichtleiter-Anordnung austritt.

The present invention relates to a light guide arrangement for use in a lighting device of a motor vehicle, which has at least one semiconductor light source. The light guide arrangement includes:

• at least one light coupling section with at least one light entry surface for coupling at least part of the light emitted by the at least one light source,
• a light decoupling section with a plurality of light decoupling elements arranged along a rear side of the light guide arrangement for deflecting at least a part of the coupled light in the direction of a lens section of the light guide arrangement, and
• the lens section, which has a longitudinal extension transverse to a light exit direction of the light guide arrangement and a convex cross section transverse to the longitudinal extension has lenticular light exit surface, via which at least part of the light deflected by the decoupling section emerges from the light guide arrangement.

Furthermore, the invention relates to a lighting device for a motor vehicle with a semiconductor light source for emitting light and at least one light guide arrangement for generating at least part of a dimmed light distribution.

Such a light guide arrangement is, for example, from the EP 0 766 037 A1 or from the EP 2 045 515 A1 known. The one from the EP 0 766 037 A1 Known light guide arrangement comprises a flat, plate-shaped light guide which is used to generate a low-beam basic light with an essentially horizontal light-dark boundary. However, the known light guide arrangement can only produce the low beam basic light if the plate-shaped light guide is arranged vertically, the outer appearance of the switched-on light guide arrangement (so-called night design) thus gives a vertically illuminated line. If the appearance of the light guide arrangement is to be a horizontally or obliquely arranged glowing line, the known light guide arrangement cannot produce a dimmed light distribution with a horizontal light-dark boundary. Rather, the light-dark boundary would always run perpendicular to the longitudinal extent of the exit surface of the light guide, ie vertically or obliquely in the case of a horizontal or obliquely oriented light guide. Another light guide arrangement according to the prior art is known from the DE-A-102012212557 known.

The present invention is therefore based on the object of designing and developing a light guide arrangement of the type mentioned at the outset such that it can produce a dimmed light distribution in which the light-dark boundary runs essentially parallel to a longitudinal extension of the light guide arrangement or a lens arrangement forming the light exit surface, so that a substantially horizontal light-dark boundary can be generated with a horizontally oriented light guide arrangement.

To achieve this object, a light guide arrangement with the features of claim 1 is proposed. In particular, when viewed in cross section, a first focal point of the lens section lies at the level of a lower edge of a coupling-out element and a second focal point is located at a large distance from the light exit surface, preferably at infinity, so that the lens section the lower edge of the coupling-out element as part of a horizontal light-dark boundary of a resulting dimmed light distribution Optical fiber arrangement depicts sharply.

With the present invention it is possible to produce a dimmed light distribution with a light-dark boundary by means of a light guide arrangement, the longitudinal extension of which runs essentially parallel to the course of the light-dark boundary. In particular, a dimmed light distribution with a horizontal light-dark boundary can be generated by a horizontally oriented light guide arrangement.

On at least one side of the light guide, for example on an end face of the light guide, the light guide arrangement has a light coupling section with at least one light entry surface. At least one light source of the lighting device is positioned in front of the at least one light entry surface. A The main emission direction of the light source is preferably arranged perpendicular to the at least one light entry surface. On its rear side, the light guide has decoupling elements which are designed, for example, as decoupling prisms. The back of the light guide is the side of the light guide that is directed against the direction of exit of light from the light guide arrangement. A light exit surface of the light guide arrangement is arranged opposite the outcoupling elements on the front of the light guide and has a lenticular cross section.

A first focal point of the lens section or the light exit surface lies on a lower edge of a coupling-out element, and a second focal point of the lens section or the light exit surface lies in infinity in the light exit direction or at a very great distance in front of the light exit surface. The decoupling elements of the decoupling section are preferably all arranged with their lower edges at the same height, that is to say on a common horizontal plane. The first focal point is located anywhere on this horizontal plane, but in any case on the lower edge of the decoupling elements.

The focal points of several cross sections through the lens section preferably lie on a focal line. The extension of the focal line runs parallel to the longitudinal extension of the lens section. The lower edges of the decoupling elements are preferably close to the focal line of the elongated lenticular light exit surface, so that the lower edges are sharp at infinity (or at a great distance from the light guide arrangement) as the essentially horizontal light-dark boundary resulting dimmed light distribution can be imaged sharply.

The light sources of the lighting device are preferably designed as semiconductor light sources, in particular as light-emitting diodes (LEDs). The light coupling section between the at least one light source and the light coupling section can be designed in a special way in order to influence the light distribution in the light guide arrangement. In particular, the light coupling section can have conically diverging reflection surfaces starting from the light coupling surface in order to achieve a collimation of the coupled light. The collimated, essentially parallel light beams then preferably strike the outcoupling elements of the outcoupling section without further reflection at outer boundary surfaces of the light guide. It is also conceivable for the coupling section to be curved, that is to say to have curved reflection surfaces.

The outcoupling elements of the light outcoupling section are preferably designed as outcoupling prisms which have a longitudinal extension and a triangular shape in a section transverse to the longitudinal extension. The longitudinal extension of the coupling prisms runs perpendicular to the main exit direction of the light from the light guide arrangement and perpendicular to the longitudinal extension of the lens section.

The decoupling prisms have a certain height h in their longitudinal extent. The height h of the prisms determines the vertical width of the resulting light distribution, especially downwards into the apron a motor vehicle equipped with the lighting device according to the invention. At the top, the light distribution is limited by the essentially horizontal light-dark boundary. The greater the prism height h is selected, the greater the vertical width of the light distribution, that is to say the more the apron is illuminated. The light distribution with regard to intensity and vertical width can be influenced by coupling prisms of different heights. For example, it is conceivable to provide coupling prisms of different heights in the coupling section of the light guide arrangement, the lower edges of the coupling prisms preferably being at the same height (in the same horizontal plane), preferably on the focal line of the first focal points of the elongated, convexly curved lenticular Light exit surface. Prism surfaces can be curved in order to scatter light passing through or to distribute them over a larger surface area.

The lens section or the convex lens-shaped light exit surface can be designed in one piece with the light guide arrangement. However, it is also conceivable that the lenticular light exit surface or the lens section and the remaining light guide arrangement comprising the at least one light coupling section and the light coupling section are designed as separate components. The convex lens-shaped light exit surface is then part of a separate lens section which is configured separately from the rest of the light guide arrangement. In particular, it is conceivable that the light guide arrangement and the lens section are separated in an essentially vertical sectional plane that is perpendicular to a main light exit direction from the light guide arrangement decoupled light and perpendicular to a horizontal cross section through the lens section. The multi-part design of the light guide arrangement according to the invention has the advantage that the light coupled into the light guide can only propagate in the light guide, so that the volume in which the light can propagate or the dimension in the cross section of the light guide in the light exit direction is reduced. This leads to the fact that the coupled-in light falls onto a decoupling element of the light decoupling section with a higher probability and frequency and is decoupled from the light guide. In general, the smaller the volume or the dimension of the light guide in the light exit direction, in particular the depth of the light guide in a main coupling direction of the light extracted from the light guide arrangement, the more light is coupled out along the same length of the light guide arrangement. Due to the depth of the light guide or the light guide cross section in the main exit direction of the light guide arrangement, the amount of light to be coupled out of the light guide arrangement can be adjusted to achieve a desired light distribution with a desired intensity profile.

The light guide arrangement can be movably arranged in a headlight or luminaire housing, so that the light-dark limit can be adjusted for basic setting, adjustment and / or headlight range control. A light distribution with a horizontal light-dark boundary can, for example, before the actual operation of the light guide arrangement, for example at the end of an assembly or production line of a headlight or a lamp, which is equipped with a light guide arrangement according to the invention, in a desired or legal given basic setting. Likewise, during the operation of the light guide arrangement, a light distribution with a horizontal light-dark limit can be adjusted in order to implement headlight range control in the vertical direction. Accordingly, the light distribution with a horizontal light-dark boundary can be adjusted in the horizontal direction during the operation of the light guide arrangement in order to implement a cornering light function.

It is conceivable that the outcoupling elements of the light outcoupling section of the light guide arrangement are designed to be of different widths, that is to say they have a different extent than seen in the longitudinal extent of the lens section. The probability and frequency that light coupled into the light guide arrangement hits a wider coupling element is greater than the probability that the coupled light hits a narrower coupling element. If a larger amount of light is to be decoupled at a certain point in the light guide arrangement, the width of the decoupling elements can be increased at this point. Accordingly, it is also conceivable to vary the distance between adjacent light decoupling elements with a constant width of the light decoupling elements in order to adjust the amount of light decoupled. In the case of coupling elements which are particularly close to one another, a larger amount of light is coupled out than if the light coupling elements are arranged at a greater distance from one another.

With a separate configuration of the light guide on the one hand and the lens section on the other hand An air gap is preferably formed between the light guide and the lens section. On the light passage surface of the coupling section, via which the light deflected by the coupling elements emerges from the light guide, and / or the light passage surface of the lens section, via which the light emerging from the light guide enters the lens section, any optically effective elements (so-called. Scattering geometries) are arranged, which scatter the light passing through, in particular in the horizontal direction.

Furthermore, it is conceivable that the depth (extension in the light exit direction) of the light guide tapers from the at least one light entry surface of the light coupling section along the longitudinal extent of the light guide, that is, viewed in the light exit direction, the light guide cross section starts from the light entry area to an opposite end of the light guide from.

It is conceivable that in the case of a multi-part configuration of the light guide arrangement with a light guide and a lens section separate therefrom, the light guide has a rectangular cross-sectional area transverse to its longitudinal extent. The cross-sectional area of the rectangular light guide is preferably of the same height as the decoupling elements. In other words, the outcoupling elements extend over the entire height of the rear side of the light guide opposite the light passage surface of the light guide. The lens section arranged at a distance from the light passage surface of the light guide preferably has a greater height than the light guide with the substantially rectangular cross-sectional area. Due to the smaller dimensions of the light guide, in particular due to its lower height compared to the lens section, there is a smaller cross-sectional area and thus a smaller volume of the light guide, so that light transported in the light guide hits a light decoupling element more often over a given length and thus more light per Length emerges from the light guide and is imaged by the lens section as a dimmed light distribution with an essentially horizontal light-dark boundary on the road in front of the motor vehicle.

The lower edge of the front light passage surface of the light guide in the light exit direction is preferably at the level of the lower edges of the decoupling elements. The focal line of the lens section with the first focal points is preferably on or in the vicinity of the lower edge of the light passage surface of the light guide. Due to the separate configuration of the light guide and the lens section, the lens section can be designed in any way without influencing the light in the light guide, in particular its transport in the light guide and its decoupling from the light guide. The cross-sectional area of the light guide can be made smaller than that of the lens section in order to improve the coupling-out efficiency.

The light guide configured separately from the lens section can be designed as a rod-shaped light guide with a cross-sectional area that is constant along its longitudinal extent or with a cross-sectional area that decreases over the longitudinal extent starting from the light entry area. It is also conceivable that instead of a rod-shaped Lichtleiters a crescent-shaped light guide is used, such as from the DE 10 2011 018 508 is known. With such a crescent-shaped light guide, light from at least one light source is collimated or parallelized by a collimator element after entering the crescent-shaped, plate-shaped light guide. The entire collimated light strikes a light outcoupling surface of the crescent-shaped light guide, through which the entire light is deflected in the direction of a light exit surface of the light guide. The deflected light hits the light passage surface of the crescent-shaped light guide so steeply that it is coupled out of the light guide and is imaged on the road in front of the motor vehicle by the lens section arranged in front of the light exit surface in order to generate the desired dimmed light distribution with a horizontal light-dark boundary. In this case too, a focal line of the lens section arranged in front of the crescent-shaped light guide runs along the lower edge of the light passage surface of the light guide, which is at the front in the light exit direction, and another focal line of the lens section runs at infinity or at a very large distance from the light exit surface of the lens section. By collimating the injected light beams in the crescent-shaped light guide, the light beams can be directed more specifically in a desired direction, so that less wasted light is produced compared to a conventional rod light guide. The entire coupled light first strikes a decoupling element before it emerges through the front light passage area and is projected onto the roadway through the lens section arranged in front of it.

With a separate configuration of the light guide and the lens section of the light guide arrangement according to the invention, the light guide can be straight, but also curved. In particular, it is conceivable that the light guide is curved in a horizontal plane, which includes the focal line of the lens section with the first focal points, in such a way that the light coupling surface of the light guide, which is at the rear in the light exit direction, has a smaller longitudinal extent than the front light passage surface of the light guide. The lens section can also be designed accordingly. It is conceivable that the curvature of the lens section is selected such that there is a substantially constant distance between the light guide or its light exit surface and the lens section over the entire longitudinal extent of the light guide arrangement. However, it would also be conceivable that the distance between the curved light guide and the curved lens section varies over the longitudinal extent, preferably either continuously increasing or continuously decreasing starting from the light entry surface of the light guide. With a varying distance between the light guide and the lens section over the longitudinal extent of the light guide arrangement, the focal length with the first focal points of the light exit surface or the lens section across the different lens cross sections could also vary, so that despite the varying distance, the focal line is always on the front the decoupling elements or on the front light passage surface of the light guide. The variation of the first focal length is conceivable both with curved light guide arrangements and with straight light guide arrangements, as long as the first focal line is at the same height the lower edge of the decoupling elements runs. Even when using a crescent-shaped light guide, as described above, it is conceivable that the distance between the light exit surface of the crescent-shaped light guide and the lens section varies.

Finally, it is also conceivable to provide not only one of the described light guide arrangements, but several in a motor vehicle lighting device. Each of the light guide arrangements operated can generate part of a dimmed light distribution. It is conceivable that a first, for example horizontally aligned light guide arrangement generates a low-beam basic light with a horizontal chiaroscuro boundary that runs essentially parallel to and just below a horizontal on a measuring screen arranged at a distance from the motor vehicle. Another light guide arrangement, which is arranged obliquely to the first light guide arrangement, preferably at a 15 ° angle to it, could be arranged next to the first light guide arrangement. The further light guide arrangement could produce a dimmed light distribution with a light-dark limit rising obliquely starting from the horizontal light-dark boundary, which preferably increases at a 15 ° angle. The further light guide arrangement could be designed to generate a low beam spot. The low beam spot could generate the rising part of a low beam distribution corresponding to the ECE regulation on the own side of the road. The two light distributions together thus produce a conventional, asymmetrical low beam corresponding to the ECE regulations with a first horizontal section on the oncoming traffic side (from the first Light guide arrangement) and a second, rising section on the own traffic side (from the further light guide arrangement).

Figur 1

eine erfindungsgemäße Beleuchtungseinrichtung eines Kraftfahrzeugs gemäß einer bevorzugten Ausführungsform;

Figur 2

eine erfindungsgemäße Lichtleiter-Anordnung als Teil einer Kraftfahrzeugbeleuchtungseinrichtung gemäß einer bevorzugten Ausführungsform in einem Querschnitt;

Figur 3

die Lichtleiter-Anordnung aus Figur 2 in einer Ansicht von vorne entgegen einer Lichtaustrittsrichtung;

Figur 4

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform in einem Querschnitt;

Figur 5

Vergleich von Lichtleitern als Teil der erfindungsgemäßen Lichtleiter-Anordnung mit unterschiedlich großen Querschnittsflächen beziehungsweise Tiefen;

Figur 6

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform mit Lichtauskoppelelementen variabler Breite in einer Ansicht von vorne entgegen einer

Figur 7

Lichtaustrittsrichtung; eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform mit einem Lichtleiter mit einer entlang einer Längserstreckung konstanten Querschnittsfläche in einer Draufsicht;

Figur 8

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform mit einer sich entlang der Längserstreckung verjüngenden Querschnittsfläche des Lichtleiters in einer Draufsicht;

Figur 9

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform in einem Querschnitt;

Figur 10

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform in einem Querschnitt;

Figur 11

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform mit einem sichelförmigen Lichtleiter in einer Draufsicht;

Figur 12

die Lichtleiter-Anordnung aus Figur 11 im Querschnitt;

Figur 13

die Lichtleiter-Anordnung aus Figur 11 mit Streuelementen auf eine Lichtdurchtrittsfläche des sichelförmigen Lichtleiters gegenüber einem Linsenabschnitt in einer Draufsicht;

Figur 14

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform im Querschnitt;

Figur 15

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform mit einem gekrümmten Lichtleiter und gekrümmtem Linsenabschnitt in einer Draufsicht;

Figur 16

zwei nebeneinander angeordnete erfindungsgemäße Lichtleiter-Anordnungen, die zueinander verkippt sind, und resultierende Lichtverteilungen auf einem Messschirm;

Figur 17

eine erfindungsgemäße Lichtleiter-Anordnung mit zwei Abschnitten und einem Knick zwischen den Abschnitten sowie von den Abschnitten erzeugte Lichtverteilungen auf einem Messschirm;

Figur 18

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform in einem Querschnitt;

Figur 19

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform in einem Querschnitt;

Figur 20

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform in einem Querschnitt;

Figur 21

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform in einem Querschnitt;

Figur 22

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform in einem Querschnitt; und

Figur 23

eine erfindungsgemäße Lichtleiter-Anordnung gemäß einer weiteren bevorzugten Ausführungsform mit einem Zusatzprisma im unteren Bereich einer Lichtaustrittsfläche des Linsenabschnitts.

Further features, embodiments and advantages of the present invention are explained in more detail below with reference to the figures. Show it:

Figure 1

an inventive lighting device of a motor vehicle according to a preferred embodiment;

Figure 2

a light guide arrangement according to the invention as part of a motor vehicle lighting device according to a preferred embodiment in a cross section;

Figure 3

the light guide arrangement Figure 2 in a view from the front against a light exit direction;

Figure 4

a light guide arrangement according to the invention according to a further preferred embodiment in a cross section;

Figure 5

Comparison of light guides as part of the light guide arrangement according to the invention with different cross-sectional areas or depths;

Figure 6

a light guide arrangement according to the invention according to a further preferred embodiment with light coupling elements of variable width in a view from the front against one

Figure 7

Light exit direction; a light guide arrangement according to the invention according to a further preferred embodiment with a light guide with a constant cross-sectional area along a longitudinal extent in a plan view;

Figure 8

a light guide arrangement according to the invention according to a further preferred embodiment with a cross-sectional area of the light guide tapering along the longitudinal extent in a plan view;

Figure 9

a light guide arrangement according to the invention according to a further preferred embodiment in a cross section;

Figure 10

a light guide arrangement according to the invention according to a further preferred embodiment in a cross section;

Figure 11

a light guide arrangement according to the invention according to a further preferred embodiment with a crescent-shaped light guide in a plan view;

Figure 12

the light guide arrangement Figure 11 in cross section;

Figure 13

the light guide arrangement Figure 11 with scattering elements on a light passage surface of the crescent-shaped light guide opposite a lens section in a plan view;

Figure 14

a light guide arrangement according to the invention according to a further preferred embodiment in cross section;

Figure 15

a light guide arrangement according to the invention according to another preferred embodiment with a curved light guide and curved lens section in a plan view;

Figure 16

two light guide arrangements according to the invention which are arranged next to one another and are tilted relative to one another, and resulting light distributions on a measuring screen;

Figure 17

a light guide arrangement according to the invention with two sections and a kink between the sections and light distributions generated by the sections on a measuring screen;

Figure 18

a light guide arrangement according to the invention according to a further preferred embodiment in a cross section;

Figure 19

a light guide arrangement according to the invention according to a further preferred embodiment in a cross section;

Figure 20

a light guide arrangement according to the invention according to a further preferred embodiment in a cross section;

Figure 21

a light guide arrangement according to the invention in accordance with a further preferred embodiment in a cross section;

Figure 22

a light guide arrangement according to the invention according to a further preferred embodiment in a cross section; and

Figure 23

a light guide arrangement according to the invention according to a further preferred embodiment with an additional prism in the lower region of a light exit surface of the lens section.

In Figure 1 A lighting device according to the invention of a motor vehicle is designated in its entirety with reference number 1. The lighting device 1 is designed as a motor vehicle headlight. Alternatively, the lighting device according to the invention could also be designed as a motor vehicle lamp, for example as a rear, front or side lamp. The lighting device 1 comprises a housing 2, which is preferably made of plastic. A light exit opening 4 formed at the front in the housing 2 in the light exit direction 3 of the lighting device 1 is closed by means of a transparent cover plate 5. The cover plate 5 can be designed as a clear plate without optically active elements or at least in some areas with optically active elements (for example cylindrical lenses or prisms) as a diffusing plate.

At least one light module can be arranged in the interior of the housing 2. In Figure 1 two light modules 6, 7 are shown as examples. The light modules 6, 7 can be arranged in the housing 2 in a fixed or pivotable manner. In particular, the light modules 6, 7 can be mounted in the housing 2 so as to be pivotable about a horizontal axis and / or to implement a cornering light function about a vertical axis. The light modules 6, 7 can be designed to generate a headlight light distribution or a part thereof. It is conceivable, for example, that the light modules 6, 7 generate one or more of the following light distributions either individually or in cooperation with one another: low beam, high beam, fog light, or any adaptive light distribution which is dependent on parameters of the motor vehicle and / or weather conditions is varied in the area surrounding the motor vehicle. Examples of adaptive light distribution are city light, country light, highway light, bad weather light, partial high beam, which corresponds to a high beam in which areas where other road users have been detected in front of the motor vehicle are shaded, or a marker light in which objects detected in front of the motor vehicle are targeted a spatially limited light beam, which is preferably arranged above a horizontal chiaroscuro boundary of a dimmed light distribution, are illuminated. The light modules 6, 7 can be designed as reflection modules or as projection modules.

Likewise arranged in the interior of the housing 2 of the lighting device 1 is a light guide arrangement according to the invention which is only shown by way of example and is shown only schematically and is designated in its entirety by reference number 10. The light guide arrangement 10 can be arranged fixed in the housing 2 or pivotable in the horizontal and / or vertical direction. In this way, a light guide arrangement 10 can also be used Cornering light function and / or headlamp leveling can be realized. The light guide arrangement 10 has a longitudinal extent 11, which is oriented essentially horizontally and, when the headlight 1 is installed in a motor vehicle, extends essentially transversely to a longitudinal axis of the vehicle. The light guide arrangement 10 serves to generate a dimmed light distribution with an essentially horizontal light-dark boundary. In this context, essentially horizontal means that the light-dark boundary runs horizontally at least in sections. This also includes what is known as an asymmetrical chiaroscuro limit, as prescribed, for example, in accordance with the relevant ECE regulations within the European Union. An asymmetrical chiaroscuro boundary comprises a horizontal section that includes an oncoming traffic lane. The horizontal section of the chiaroscuro boundary prevents oncoming road users from being dazzled. On the own traffic side, the asymmetrical chiaroscuro limit has a higher section in order to improve the visibility for the driver of the motor vehicle. The higher section of the light-dark boundary preferably also has a horizontal course. However, it is also conceivable that the higher section of the asymmetrical chiaroscuro boundary has an obliquely increasing course and, starting from the horizontal section, rises, for example, at a 15 ° angle. An intermediate section of the asymmetrical light-dark boundary can be provided between the horizontal section on the oncoming traffic side and the elevated section on the own traffic side, which section runs, for example, vertically or obliquely, in particular at a 15 ° angle.

The light guide arrangement 10 is particularly preferred for Generation of a low-beam light, which has a horizontal chiaroscuro limit across its entire width, which runs on a measuring screen arranged at a distance from the headlight 1, just below and parallel to a horizontal line. Furthermore, the low-beam light has a relatively large horizontal extent and no pronounced, spatially limited intensity maxima. The low beam basic light can be part of a conventional low beam distribution according to ECE regulation with asymmetrical light-dark limit. In order to implement the ECE low beam, the low beam basic light can be superimposed by a so-called low beam spot which has a smaller width than the low beam basic light, pronounced intensity maxima in the center of the low beam spot and an obliquely increasing light-dark limit. The low beam spot generates the intensity maxima in the center of the resulting low beam distribution according to ECE regulation as well as the higher section of the cut-off line on the own traffic side. The low beam basic light, on the other hand, ensures sufficient side illumination of the resulting low beam distribution in accordance with ECE regulation.

Based on Figures 2 and 3 A first preferred exemplary embodiment of a light guide arrangement 10 according to the invention is explained in more detail. In this exemplary embodiment, the light guide arrangement 10 is formed in one piece, that is to say a light guide section 12 for transporting coupled light along the longitudinal extent 11 of the light guide arrangement 10 and for decoupling the light from the light guide section 12 and a lens section 13 for imaging the light from the Light guide section 12 on the road in front of the motor vehicle to generate the desired resulting dimmed light distribution are designed as a common, integral component.

The light guide arrangement 10 comprises at least one light source 14, which comprises one or more semiconductor light sources, in particular in the form of light-emitting diodes (LEDs). The light guide arrangement 10 has a light coupling section 15 with at least one light entry surface 16 for coupling at least part of the light emitted by the at least one light source 14. Furthermore, the light guide arrangement 10 comprises a light coupling section 17 with a plurality of light coupling elements 18 arranged along a rear side of the light guide arrangement 10 for deflecting at least part of the coupled light in the direction of the lens section 13 of the light guide arrangement 10. The lens section 13 has an im Cross section transverse to the longitudinal extent 11 (cf. Fig. 2 ) convex lens-shaped light exit surface 19, via which light deflected by the coupling-out section 17 exits the light guide arrangement 10. In the example shown, the lens section 13 comprises, for example, a cylindrical lens. The cylindrical lens can have identical, but also different focal lengths over its longitudinal extension 11. The cross section of the lens section 13 has a first focal point 20 on the object side and a second focal point 21 on the image side. All first focal points 20 of the lens section 13 of the different cross sections along the longitudinal extension 11 of the light guide arrangement 10 lie on a focal line. If the lens section 13 has the same focal lengths over its longitudinal extent 11, the focal line is a straight line. If the focal lengths vary over the longitudinal extent 11 of the lens section 13, the focal line forms any other curved line. An essential aspect of the present invention is that viewed in a cross section of the light guide arrangement 10, the first focal point 20 of the lens section 13 or the light exit surface 19 lies at the level of a lower edge of a decoupling element 18 of the decoupling section 17. The focal point 20 is therefore at the same height as the lower edge of the decoupling element 18. As a result, the lens section 13 or the light exit surface 19 sharply reproduces the lower edge of the decoupling element 18 as part of a horizontal chiaroscuro boundary of the resulting dimmed light distribution on the road ahead of the motor vehicle. In this way, a light-dark boundary can be generated with the light guide arrangement 10, the course of which is essentially parallel to the longitudinal extent 11 of the light guide arrangement 10. It is very particularly preferred if the first focal points 20 of different cross sections of the light exit surface 19 or of the lens section 13 lie on a focal line which runs along the lower edge of the decoupling elements 18, so that the light exit surface 19 or the lens section 13 defines the lower edge of the decoupling elements 18 as horizontal Shows the light-dark boundary of the resulting dimmed light distribution. The relationship between the object-side focal point 20 and the image-side focal point 21 is thus described. The two focal points 20, 21 represent the image on the optical axis 22 of the lens section 13. The focal point 20 on the object side can lie on the lower edge of a coupling-out element 18.

In particular, it is proposed that the first focal point 20 be on a front side of the coupling-out element 18 directed in the light exit direction 3. Furthermore lies in In cross section, a second focal point 21 is viewed at a large distance from the light exit surface 19 of the lens section 13 or even at infinity.

While the lower edges of the individual decoupling elements 18 preferably lie in a common, preferably horizontally oriented plane, a height h of the individual decoupling elements 18 can be varied as desired. By varying the height h of the decoupling elements 18, it can be set how far the resulting dimmed light distribution shines downwards, that is to say how close to the motor vehicle the area in front of the vehicle is illuminated. Greater heights h of the decoupling elements 18 lead to a stronger illumination of the apron up to the front of the vehicle.

The light coupling section 15 can be specially shaped to influence the light distribution in the light guide section 12. For example, it would be conceivable that the coupling section 15 has conically diverging reflection surfaces starting from the entry surface 16 (cf. Figure 3 ) to collimate the light. It would also be conceivable for the coupling section 15 to be curved.

The resulting dimmed light distribution with regard to intensity maxima, vertical width and vertical course of the intensity distribution can be influenced by coupling elements 18 of different heights. In Figure 3 For example, decoupling elements 18 are shown with different heights h, decoupling elements 18 'having the greatest height h ₁ , decoupling elements 18 "average heights h ₂ and decoupling elements 18'" having smaller heights h ₃ (h ₁ > h ₂ > h ₃ ). It can be clearly seen that the lower edges of the Coupling elements 18 ', 18 ", 18'" lie on a common plane.

The outcoupling elements 18 are designed, for example, as outcoupling prisms that have a longitudinal extent that preferably extends perpendicular to a horizontal plane comprising an optical axis 22 of the light guide arrangement 10. A longitudinal extension of the decoupling prisms 18 is shown in FIG Figure 3 designated by way of example with the reference symbol 23. The longitudinal extension 23 of the coupling-out prisms 18 runs perpendicular to the longitudinal extension 11 of the light guide arrangement 10.

In Figure 4 A further exemplary embodiment of a light guide arrangement 10 according to the invention is shown. The light guide section 12 and the lens section 13 are designed as separate components. The two sections 12, 13 are preferably separated from one another along a vertical sectional plane. The section plane runs perpendicular to the light exit direction 3 of the arrangement 10 and perpendicular to the horizontal plane comprising the optical axis 22. An air gap 24 is preferably formed between the two sections 12, 13. This means that the light transported along the light guide section 12 and deflected by means of the decoupling elements 18 emerges from the light guide section 12 via a light passage surface 24 ′ opposite the decoupling section 17. After passing through the air gap 24, the emerged light then enters the lens section 13 via a light passage surface 24 ″. The physical division of the light guide arrangement 10 into sections 12, 13 can significantly improve the efficiency of the light guide arrangement 10 Light guide section 12 serves exclusively for transporting the coupled light along the longitudinal extent 11 of the light guide arrangement 10 and for coupling out the coupled light. The coupled-in light transported in the light guide section 12 along the longitudinal extent 11 of the light guide arrangement 10 is preferably reflected by means of total reflection at the outer boundary surfaces of the light guide section 12. When the light beams strike a coupling-out element 18 of the coupling-out section 17, they are deflected in such a way that they hit the outer boundary surfaces more steeply and exit through the light guide section 12 through them. Of course, it is also conceivable for the outer boundary surfaces of the light guide section 12 to be at least partially mirrored.

In contrast, the lens section 13 only serves to image the light emerging from the light guide section 12 on the road in front of the motor vehicle and to generate the resulting light distribution. In this embodiment too, the lens section 13 viewed in cross section (cf. Figure 4 ) a first focal point 20, which is arranged at the level of the lower edge of the decoupling elements 18 of the decoupling section 17 and preferably on the front of the decoupling elements 18. A second focal point 21 of the lens section 13 lies at infinity or at a great distance from the light exit surface 19. In this way, the lens section 13 can depict the lower edges of the light coupling elements 18 as a light-dark boundary of the resulting light distribution in the infinity.

By dividing the light guide arrangement 10 into two Sections 12, 13 reduce the area (the light guide section 12) in which the coupled light can propagate along the longitudinal extent 11 of the light guide arrangement 10, and the light strikes one of the waves with a higher probability and thus also with a greater frequency Coupling elements 18 and is coupled out of the light guide section 12. In general, the smaller a depth t of the light guide cross section in the light exit direction 3, the more light is coupled out along the same length 1 as seen in the longitudinal extent 11. This principle is based on the Figure 5 illustrated. Figure 5 shows two light guides 12 'and 12 ", which have different depths t ₁ and t _2. The lengths l ₁ and l _{2 of} the two light guides 12', 12" are identical (l ₁ = l ₂ and t ₁ <t ₂ ). It can be clearly seen that a light beam transported along the longitudinal extent 11 of the light guides 12 ′, 12 ″ hits the coupling-out section 17 more often when the depth t of the light guide 12 is small. In the example shown, the light beam 11 ′ drawn in by way of example applies the narrower light guide with the depth t ₁ hits the coupling-out section 17 twice, whereas the light beam 11 "in the case of the deeper light guide 12" with the depth t ₂ only hits the coupling-out section 17 once. Through the narrower light guide 12 'with the lower depth t ₁ more light can be coupled out over the same length l ₁ = l ₂ .

Figure 6 shows a further embodiment of a light guide arrangement 10, which has coupling-out elements 18 with variable width. The light guide arrangement 10 is in Figure 6 shown from the front, that is against a light exit direction 3.

In the Figures 7 and 8 Other embodiments of the light guide arrangement 10 according to the invention are shown in a plan view. The light guide arrangement 10 is formed in two parts and has a light guide section 12 and a separate lens section 13, between which an air gap 24 is formed. The light guide section 12 from Figure 7 has a constant depth t as seen over the longitudinal extent 11 of the light guide arrangement 10. In contrast, the light guide arrangement 10 shows Figure 8 the light guide section 12 has a tapering depth t starting from the light entry surface 16 or the light coupling section 15 over the longitudinal extent 11. In this way it can be ensured that up to the end of the light guide section 12, which is opposite the light entry surface 16, all the light coupled into the light guide section 12 has been coupled out of the latter. The efficiency of the arrangement 10 can thereby be improved.

In Figure 9 A further embodiment of the light guide arrangement 10 according to the invention is shown. To further improve the efficiency of the light guide arrangement 10, the light guide section 12 has a reduced height, which corresponds to the height h of the coupling elements 18 of the coupling section 17. Thus, on the back of the light guide section 12, the light decoupling section 17 with the light decoupling elements 18 is formed over the entire height of the back. A special feature of this embodiment provides that, in a cross section of the lens section 13, the first focal point 20 is still on the lower edge of the decoupling elements 18, but not on the front of the Coupling elements 18, but is arranged on a front light passage surface 24 'of the light guide section 12. The lower edge of the light passage surface 24 'of the light guide section 12 is thus sharply imaged by the lens section 13 to generate the light-dark boundary of the resulting light distribution.

A further preferred embodiment of the light guide arrangement 10 according to the invention is described below with reference to FIG Figures 11 to 13 explained in more detail. The arrangement 10 is also formed in several parts and has a light guide section 12 and a lens section 13 separate therefrom. The light guide section 12 is instead of rod-shaped (cf. Figures 2 to 10 ) crescent-shaped. Such a light guide arrangement 10 is, for example, from the DE 10 2011 018 508 is known to which reference is made with regard to the structure and mode of operation of the crescent-shaped light guide 12 or the entire light guide arrangement 10. The content of the DE 10 2011 018 508 is incorporated by reference into the present application. The crescent-shaped light guide 12 has at least one light entry surface 16 facing the semiconductor light source 14, via which at least some of the light emitted by the semiconductor light source 14 is coupled into the light guide 12. The light entry surface 16 preferably runs perpendicular to a main emission direction of the semiconductor light source 14, but it can also be inclined to the main emission direction.

Furthermore, the crescent-shaped light guide section 12 comprises two opposing boundary surfaces 25, each forming a base area, with totally reflecting properties for reflecting at least a part of the coupled light. In the top view ( Figures 11 and 13 ) only the upper of the two interfaces 25 is visible. At the interfaces 25, light rays that strike flatly are reflected by total reflection. Furthermore, the light guide 12 in the area of the light coupling section 15 comprises at least one collimator element 26 for bundling at least part of the coupled light. The collimator element 26 has a top view (cf. Figures 11 and 13 ) parabolic reflection surface. In a cross section perpendicular to the plane of the drawing Figures 11 and 13 the collimator element 26 has either a flat or an arched shape. Incident light beams can be reflected on the collimator element 26 by means of total reflection or conventional specular reflection. In addition, the light guide 12 has a light passage surface 24 '(cf. Figure 13 , Section A), through which steeply incident light rays are coupled out. Finally, the light guide 12 comprises a coupling-out section 17 for deflecting at least a part of the coupled-in light in the direction of the light passage surface 24 '. The light decoupling section 17 comprises a multiplicity of decoupling elements 18, which are designed, for example, as prisms, reflector surfaces or deflecting mirrors, which deflect the light in the direction of the light passage surface 24 '.

The light can be deflected at the light decoupling element 17 either by normal reflection or else by total reflection. In the event of reflection by reflection, the outside of the light guide 12 is preferably provided with a reflective coating in the region of the light decoupling elements 18. The lens section 13 for beam shaping is arranged in the beam path of the outcoupled light. The lens section 13 is in the illustrated embodiment formed as a cylindrical lens with a longitudinal extension 11.

A section through the crescent-shaped light guide section 12 in the plane of the drawing Figures 11 and 13 is also called the meridional cut. A section through the crescent-shaped light guide 12 in the plane of the drawing Figure 12 , that is perpendicular to the plane of the drawing Figures 11 and 13 , is also referred to as a sagittal section. The meridional cut thus runs along a longitudinal or surface extension of the light guide 12. The sagittal cut runs along a transverse extension of the light guide 12. The meridional cut and the sagittal cut run perpendicular to one another. Both the meridional section and the sagittal section contain the optical axes of the light guide 12. The crescent-shaped light guide 12 comprises different optical axes, for example a main emission direction 27 of the semiconductor light source 14, which corresponds to a light coupling direction of the light into the light guide 12, an optical axis 22 of the light guide 12 , and the light exit direction 3.

The mode of operation of the crescent-shaped light guide section 12 or the light guide arrangement 10 according to the invention is described in more detail below. The at least one semiconductor light source 14 emits a light beam in the main emission direction 27 into a 180 ° half-space above the light source 14. At least some of the emitted light beams enter the light guide 12 as a divergent beam 28 ′ through the light entry surface 16 and then strike the collimator element 26. When the light beams enter the light guide 12, the light is refracted at the entry surface 16. The corresponding beam path in the meridional section is in Figure 11 drawn as an example. The collimator element 26 collimates the initially divergent beam 28 'in the meridional section as best as possible (parallelized), ie the diagonal of the beam is reduced. In Figure 11 the parallelized light rays 28 "are clearly visible.

The light beams 28 ″ directed in this way spread largely rectilinearly in the meridional section of the light guide 12. In the sagittal section, however, the light beams 28 ″ are preferably not yet bundled or parallelized, in particular if the collimator element 26 is a flat surface in cross section, so that the light beams 28 "on their way from the collimator element 26 to the outcoupling section 17 can be reflected one or more times between the opposite interfaces 25 of the light guide 12. The light beams 28" hit the outcoupling section 17 or the outcoupling elements 18 formed there the decoupling elements 18 are designed as stair-shaped deflecting mirrors which are inclined by approximately 45 ° to the main light exit direction 3. The light decoupling section 17 deflects the beam path 28 ″, so that the deflected light beams 28 ′ ″ strike the light passage surface 24 ′ of the light guide section 12 approximately perpendicularly and exit from the light guide 12. The light rays that have emerged enter the lens section 13 via the light passage surface 24 ″. Since the light rays 28 ′ ″ run largely parallel in the meridional section, the light section 13 in the meridional section practically does not bundle the light that passes through. The lens section 13 forms the lower edges of the decoupling elements 17 as the light-dark boundary of the dimmed light distribution at infinity or at a great distance from the light guide arrangement 10.

Viewed in the sagittal section, the light beams emitted by the at least one semiconductor light source 14 are refracted at the entry surface 16 upon entry into the light guide 12, and the divergent beam bundle in the light guide 12 is passed on by a large number of total reflections between the two approximately parallel boundary surfaces 25 of the light guide 12. In the sagittal section, the injected light is thus guided between two largely parallel surfaces 25 in the manner typical of light guides by means of multiple total reflections. The light beams finally strike the light coupling-out section 17 or the reflectors / deflecting mirrors 18, are deflected in the direction of the light passage surface 24 ′ and exit the light guide 12 through this.

The light rays 28 ″ pass through the passage surface 24 ′, viewed in the sagittal section, obliquely or inclined to the surface 24 ′, so that the decoupled light forms a divergent light bundle in the sagittal section decoupled light rays 28 '"in sagittal section. When the light passes through the lens section 13, the opening angle of the light bundles through the cylindrical lens 13 thus decreases. With the light guide arrangement 10 according to the invention, it is therefore possible for the bundle of the coupled-in light 28 ′ in the meridional section with the aid of the collimator element 26 on the light coupling-in section 15 to bundle, while in the sagittal section largely no focus within the Light guide section 12 takes place.

Of course, it is also conceivable that the collimator element 26 focuses not only in the meridional section, but also in the sagittal section. For this purpose, the collimator element 26 can also have the shape of a parabola or a circular section in cross section. The collimator element 26 is preferably convexly curved in cross section. As a result, the reflected light rays 28 ″ would also be bundled in the sagittal section and, for example, would even run essentially parallel to one another and, on their way to the coupling-out element 17, would rarely - if at all - hit one of the interfaces 25 and be reflected by them.

The light guide arrangement 10 according to this exemplary embodiment has the advantage that due to the very directional beam path in the meridional section (cf. Figure 11 ) it is possible through specific coordination of the collimator element 26 and the coupling-out section 17 to achieve a very good homogeneity in the appearance of the light guide section 12. The bundling of the light beams by the lens section 13 in the sagittal section brings about focusing and thus an improvement in the optical efficiency of the light guide arrangement 10. It is also particularly advantageous that the light guide section 12 can be realized with particularly small wall thicknesses (distance between the side surfaces 25).

On at least part of at least one of the light passage surfaces 24 '; 24 "(cf. Figure 13 ) of the outcoupling section 17 or the light guide section 12 and / or the lens section 13, optically active elements 24 '' can be arranged which scatter the light passing through, in particular in the horizontal direction Figure 13 Scattering optics 24 '"in the form of pillow optics or cylindrical lenses are formed on the light passage surface 24', for example.

Figure 14 shows a further variant of a light guide arrangement 10 for producing a dimmed light distribution, for example a low beam basic light, here also the light guide section 12 being formed separately from the lens section 13. The lens section 13 does not have the shape of a cylindrical lens, but is designed differently. Furthermore, the lens section 13 is arranged at a greater distance from the light passage surface 24 ′ of the light guide section 12. In addition, the light guide arrangement 10 has a light guide section 12 with two superimposed collimator elements 26, which are designated by 26 'and 26 ". The collimator elements 26' and 26" direct the collimated light onto a common coupling-out section 17 of a common part of the light guide section 12. Here too, the first focal point 20 or the corresponding focal line of the lens section 13 is arranged at the level of the lower edge of the coupling-out elements 18 of the coupling-out section 17. In the example shown, the first focal point 20 or the corresponding focal line is positioned on the front light passage surface 24 ′ of the light guide section 12.

Figure 15 shows an exemplary embodiment with a rod-shaped light guide section 12 curved in the horizontal plane comprising the optical axis 22. The lens section 13 is curved in a corresponding manner, so that a Air gap 24 between the two sections 12, 13 preferably has a constant width over the entire longitudinal extent 11 of the light guide arrangement 10. With a varying focal length of the different cross sections of the lens section 13, the lens section 13 can also have a different curvature than the light guide section 12, so that the distance between the two sections 12, 13 in the area of the air gap 24 along the longitudinal extent 11 also varies.

It is also conceivable to arrange a plurality of the individually described light guide arrangements 10 next to one another or one above the other in a lighting device 1. Such an exemplary embodiment with two light guide arrangements 10 arranged next to one another is shown in FIG Figure 16 shown. In this case, one of the light guide arrangements, namely the light guide arrangement 10 ′, is arranged in the lighting device 1 with a substantially horizontal longitudinal extent 11 a. The other light guide arrangement 10 "is arranged with a longitudinal extent 11b tilted at an angle α with respect to the longitudinal extent 11a of the first light guide arrangement 10 '. The angle α is preferably 15 °. At a distance from the lighting device 1 or the light guide arrangements 10 ', 10 "a measuring screen 29 is arranged. A horizontal 30 and a vertical 31 are shown on the measuring screen 29. Although the Figures 16 and 17 each show two measuring screens, it is always the same measuring screen 29, on the one hand the light distribution 32 generated by the first light guide arrangement 10 'and on the other hand the light distribution 33 generated by the second light guide arrangement 10 "is shown.

The first resulting light distribution 32 is on Low beam basic light, which has a relatively large horizontal scatter and thus ensures good illumination of the side areas. The low beam basic light 32 has a horizontal chiaroscuro boundary that runs completely below the horizontal 30. Areas of the same illuminance are designated by so-called isolux lines 34. It can be clearly seen that an area 35 with particularly large illuminance values extends just below the light-dark boundary and over a large part of the horizontal extent of the light distribution 32. The low beam basic light 32 therefore has no pronounced intensity maxima. The second resulting light distribution 33 is a low beam spot which has a smaller horizontal extent than the low beam basic light 32 and pronounced intensity maxima in a central region 36 of the light distribution 33. In addition, the light distribution 33 has a chiaroscuro limit which is at a 15 ° angle to the horizontal 30 rises and runs approximately through an intersection between the horizontal 30 and the vertical 31. The low beam spot enables particularly high illuminance values to be achieved in the center of a resulting overall light distribution.

The two light distributions 32, 33 overlap to produce the resulting total light distribution, for example an asymmetrical low beam distribution according to the ECE regulation. Of course, it is also conceivable to generate other light distributions 32, 33 by suitable design of the light guide arrangements 10 ', 10 ", which then overlap to other overall light distributions, for example a low beam light distribution according to the SAE regulation (for the USA), the TRIAS regulation (for Japan) or the CCC regulation (for China).

The two separate light guide arrangements 10 'and 10 " Figure 16 can also be combined to form a common, bent light guide arrangement 10 with sections 10 '"and 10"". Such an embodiment is shown in FIG Figure 17 shown. The sections 10 ′ ″, 10 ″ ″ generate the light distributions 32, 33 in accordance with the light guide arrangements 10 ′, 10 ″ in the manner described above.

In Figure 18 A further exemplary embodiment of the invention is shown, the light guide arrangement 10 having a thin rectangular light guide section 12 with a roller-like lens as the lens section 13 for focusing.

In Figure 19 A further exemplary embodiment of the invention is shown, the light guide arrangement 10 having a thin rectangular light guide section 12 with a focusing reflector 13a for focusing.

In Figure 20 A further exemplary embodiment of the invention is shown, the light guide arrangement 10 having a thin rectangular light guide section 12 with a roller-like lens as the lens section 13 for focusing, wherein a light exit surface of the lens 13 is tilted with respect to the optical axis 22 of the arrangement 10.

In Figure 21 A further exemplary embodiment of the invention is shown, the light guide arrangement 10 being two thin rectangular light guide sections 12 ′, 12 ″ arranged next to one another or one above the other, with roller-like light disks as lens sections 13 ′, 13 ″. to focus on. The two roller-like light disks 13 ', 13 "are combined to form a common component. However, it would also be conceivable for them to be formed separately from one another.

In order to influence the resulting light distribution 32, 33 of the light guide arrangement 10, various structures, recesses or bulges can be attached to the light guide section 12. One such example is in Figure 22 shown. The light guide arrangement 10 has a thin rectangular light guide section 12 with a roller-like lens as a lens section 13 for focusing. On the top of the light guide section 12, a flattened portion 12a is formed for designing the light distribution.

The resulting light distribution 32, 33 of the light guide arrangement 10 can also be influenced in that various types of structures, recesses or bulges are formed on the lens section 13. One such example is in Figure 23 shown. In the lower region, the lens section 13 has an additional prism 13b for shaping the light distribution, through which light passing through is deflected downward, for example into the apron.

Furthermore, the coupling-out prisms 18 on the light coupling-out section 17 can be tilted forward (and below) by an angle α with respect to a vertical (cf. Figures 10 and 23 ). This allows light in the light distribution to be shifted to a desired position. The reference numeral 37 denotes a retaining pin.

Claims (17)

1. Light guide arrangement (10) for use in a lighting device (1) of a motor vehicle, wherein the lighting device (1) comprises at least one semiconductor light source (14), the light guide arrangement (10) comprising:

   - at least one light input section (15) having at least one light input surface (16) for inputting at least part of the light emitted by said at least one light source (14),

   - a light output coupler section (17) having a plurality of light output coupler elements (18) arranged along a rear side of the light guide assembly (10) for deflecting at least a part of the input light towards a lens section (13) of the light guide assembly (10), and

   - the lens section (13), which has a longitudinal extension (11) transverse to a light exit direction (3) of the light guide arrangement (10) and a lenticular light exit surface (19) which is convex in a cross-section transverse to the longitudinal extension (11) and via which at least part of the light deflected by the output coupler section (17) exits the light guide arrangement (10),

   wherein, viewed in cross-section, a first focal point (20) of the lens section (13) is located at the level of a lower edge of an output coupler element (18) and a second focal point (21) is located at a large distance from the light-exit surface (19), so that the lens section (13) sharply images the lower edge of the output coupler element (18) as part of a horizontal light-dark boundary of a resulting low beam light distribution (32; 33) of the light guide arrangement (10), characterized in that a plurality of first focal points (20) of different cross-sections of the lens section (13) lie on a focal line which runs along the lower edges of the output coupler elements (18), and in that the output coupler elements (18) are all arranged with their lower edges on a common horizontal plane which is arranged in such a way with respect to the focal line of the lens section (13), that the lens section (13) sharply images the lower edges of the output coupler elements (18) as the horizontal light-dark boundary of the resulting low beam light distribution, and in that the output coupler section (17) and the lens section (13) are designed as separate components, a subdivision of output coupler section (17) and lens section (13) running along the longitudinal extension (11) of the lens section (13) and transversely to the light exit direction (3) of the light guide arrangement (10).
2. Light guide arrangement (10) according to claim 1, characterised in that, viewed in cross-section, the first focal points (20) of the lens section (13) lie on a front side of the output coupler element (18) directed in the light exit direction (3).
3. Light guide arrangement (10) according to claim 1 or 2, characterised in that the output coupler elements (18) are constructed as prisms, the longitudinal extension (23) of which runs transversely to the longitudinal extension (11) of the lens section (13) and to the light exit direction (3) of the light guide arrangement (10).
4. Light guide arrangement (10) according to any one of claims 1 to 3, characterised in that a height (h) of the output coupler elements (18) is selected in such a way that the resulting low beam light distribution (32; 33) has a predetermined vertical extension after exit from the light guide arrangement (10).
5. Light guide arrangement (10) according to any one of claims 1 to 4, characterized in that a height (h) of the output coupler elements (18) is selected differently, the lower edges of the output coupler elements (18) all being arranged on the common horizontal plane.
6. Light guide arrangement (10) according to any one of claims 1 to 5, characterized in that a height (h) of the output coupler elements (18) is alternately selected higher and lower.
7. Light guide arrangement (10) according to any one of claims 1 to 6, characterized in that the at least one light input section (15) and the light output coupler section (17) are formed in one piece as an integral component (12).
8. Light guide arrangement (10) according to any one of claims 1 to 7, characterized in that the subdivision of the output coupler section (17) and the lens section (13) runs in a vertical sectional plane parallel to the longitudinal extension (11) of the lens section (13).
9. Light guide arrangement (10) according to any one of claims 1 to 8, characterized in that an air gap (24) is formed between a light passage surface (24') of the output coupler section (17), via which the light deflected by the output coupler elements (18) emerges from the output coupler section (17), and a light passage surface (24") of the lens section (13), via which the light emerging from the output coupler section (17) enters the lens section (13).
10. Light guide arrangement (10) according to claim 9, characterized in that optically active elements (24'") are arranged on at least part of at least one of the light passage surfaces (24'; 24") of the output coupler section (17) and/or of the lens section (13), which elements scatter the light passing through, in particular in the horizontal direction.
11. Light guide arrangement (10) according to any one of claims 1 to 10, characterized in that the output coupler section (17) has a longitudinal extension which runs essentially parallel to the longitudinal extension (11) of the lens section (13), and in that a cross-sectional area of the light output coupler section (17), which runs transversely to its longitudinal extension, decreases from the light input section (15) over the longitudinal extension of the light output section.
12. Light guide arrangement (10) according to any one of claims 1 to 11, characterised in that the at least one light input section (15) has means (26) for focusing the input light.
13. Light guide arrangement (10) according to claim 12, characterized in that the means (26) for focusing comprise reflecting surfaces which are arranged on opposite sides of a light entry surface (16) of the at least one light input section (15) and diverge conically, or an optical attachment made of a transparent material, which has a central lens and totally reflecting boundary surfaces surrounding the latter, a focusing of the input light by the optical attachment taking place by means of refraction at a light entry surface and/or total reflection at the boundary surfaces.
14. Light guide arrangement (10) according to any one of claims 1 to 13, characterised in that the light guide arrangement (10) has exactly one light input section (15) and that the input section (15) and the light output coupler section (17) are formed as a flat, sickle-shaped light guide (12) with a surface extension which runs in a plane which is parallel to the light exit direction (3) of the light guide arrangement (10) and perpendicular to the cross-section of the lens section (13).
15. Light guide arrangement (10) according to any one of claims 1 to 14, characterized in that the light guide arrangement (10) is designed to produce a part (32; 33) of a low beam light distribution, in particular a low beam light basic light (32) with a relatively large horizontal scattering and without pronounced intensity maxima or a low beam light spot (33) with a small horizontal scattering and pronounced intensity maxima approximately in the centre (36) of the light distribution (33).
16. Lighting device (1) for a motor vehicle, having at least one semiconductor light source (14) for emitting light and at least one light guide arrangement (10) for generating at least part of a low beam light distribution, characterized in that the light guide arrangement (10) is designed according to one of the preceding claims.
17. A lighting device (1) according to claim 16, characterized in that the lighting device (1) comprises a plurality of light guide arrangements (10', 10") according to claim 17, wherein the longitudinal extension (11a) of one light guide arrangement (10') is substantially horizontal and the longitudinal extension (11b) of another light guide arrangement (10") is oblique thereto, preferably at an angle of 15°, wherein the horizontal light guide arrangement (10') is designed to produce a basic low beam light (32) and the oblique light guide arrangement (10") is designed to produce a low beam spot (33).

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